title: Design of an implantable seismic sensor placed on the ossicular chain.
abstract: This paper presents a design guideline for matching a fully implantable middle ear microphone with the physiology of human hearing. The guideline defines the first natural frequency of a seismic sensor placed at the tip of the manubrium mallei with respect to the frequency-dependence hearing of the human ear as well as the deflection of the ossicular chain. A transducer designed in compliance with the guideline presented reduces the range of the output signal while preserving all information obtained by the ossicular chain. On top of a output signal compression, static deflections, which can mask the tiny motions of the ossicles, are reduced. For guideline verification, a microelectromechanical system (MEMS) based on silicon on insulator technology was produced and tested. This prototype is capable of resolving 0.4 pm/Hz with a custom made read-out circuit. For a bandwidth of 0.1 kHz, this deflection is comparable with the lower threshold of speech (≈ 40 phon).
authors.affiliation: Institute for Integrated Sensor Systems, Austrian Academy of Sciences, 2700 Wiener Neustadt, Austria. matthias.sachse@oeaw.ac.at
authors.forename: M
authors.initials: M
authors.lastname: Sachse
authors.forename: W
authors.initials: W
authors.lastname: Hortschitz
authors.forename: M
authors.initials: M
authors.lastname: Stifter
authors.forename: H
authors.initials: H
authors.lastname: Steiner
authors.forename: T
authors.initials: T
authors.lastname: Sauter
mesh_terms: D001696:Biomechanical Phenomena; D004429:Ear Ossicles / Q000033:anatomy & histology; D055615:Electrical Equipment and Supplies; D006801:Humans; D008953:Models, Anatomic; D009998:Ossicular Prosthesis; D011474:Prosthesis Design / Q000379:methods*; D059629:Signal-To-Noise Ratio
keywords: Implant; MEMS; Middle ear microphone; Seismic sensor